You could have downloaded Opusmodus 1.0.15652 for Mac from our software library for free. The software relates to Audio & Video Tools. The actual developer of this software for Mac is MMXIV Opusmodus™ Ltd. The most popular version among the application users is 1.0. This application was developed to work on Mac OS X 10.7 or later. The application's installer is commonly called opusmodus.dmg.
From the developer:
Opusmodus is an application designed for music composition. At the heart of Opusmodus is the Composer panel. This is where the script for a new piece of music comes together. It starts as a blank page, but composers quickly learn to fill it with expressions that can be seen as a score, auditioned, shown as notation or visualized graphically.
You may want to check out more Mac applications, such as V-Synth Librarian, Mandala Virtual Brain or SongScreen Liquid, which might be similar to Opusmodus.